Forks in trees
Test forks
Cultivating Complexity Robot testing
3 point system
Forester input
25 forks felled
.3DM Fork photos
Forks Traced
Fork analysis script
Fork cutting list
GPS data
Truss Mockup
Organization 3
Organization 2 Organization 1
Engineer input
Vierendeel truss
.3DM Truss volume 1
.3DM Not enough forks
Catenary arch
Truss volume 2
DESIGN NOTES The Tree Fork Truss employs twenty distinct beech forks within an arched vierendeel truss. An intentionally unusual arrangement for timber, its non-triangulated form is
Zachary Mollica
specifically enabled by the rigidity of these naturally formed joints.
Project brief
Larch poles
Field grown oak
2
Introduction Digital design and fabrication tools are often used to develop nonstandard series of components from standardized materials. In the case of wooden building, timber is reduced to sheets and sticks before having a complexity returned to it by milling procedures. And yet, trees and other such organic materials already present a naturally formed nonstandard series – each wholly unique. In The Alphabet and the Algorithm, Mario Carpo proposes that digital tools might allow: “a nimbler exploitation of organic building materials like timber or stone, which may be structurally unpredictable due to natural variations. Nonstandard technologies could interact with such irregularities, and adapt form and design to the variability of nature almost as aptly as artisanal manipulation once did.” The primary structure of the Wood Chip Barn is a robotically fabricated, arched Vierendeel like truss composed of twenty distinct tree forks. This work demonstrates clearly that digital tools are well suited to processing these inherent forms - creating strong, and complex ‘components’ with minimal energy. While some version of the structure might have been achieved without digital technologies, the efficiency and intelligence which they afforded us could not. Outlined on page 8, bringing tree forks from standing in the forest to within the truss required the development of an innovative, digitally informed workflow. This text expands a number of parts of this process in which I was directly involved. – Zachary Mollica.
3
4
5
Photo: Valerie Bennett
6
7
Forks in trees
Test forks
Robot testing
3 point system
Forester input
25 forks felled
.3DM Fork photos
Forks Traced
Fork analysis script
Fork cutting list
GPS data
Truss Mockup
Organization 3
Organization 2 Organization 1
Engineer input
Vierendeel truss
.3DM Truss volume 1
.3DM Not enough forks
Catenary arch
Truss volume 2
DESIGN NOTES The Tree Fork Truss employs twenty distinct beech forks within an arched vierendeel truss. An intentionally unusual arrangement for timber, its non-triangulated form is
8
Project brief
specifically enabled by the rigidity of these naturally formed joints.
Larch poles
Tool path script
Tools paths
Robot cell prepared
FABRICATION NOTES With a final truss organization selected, the robotic arm machined connection
3D scanning
geometries in to each fork to
Robot fabrication
define their relationships to each other. While digitally fabricated, the truss was pre-assembled in two halves in the Big Shed before eventually being erected on site. Connection script
.3DM
Connection mockup
Truss Organized
17 iterations
Scaffold design
Engineer input
Final truss model
.3DM Assembly jig
Final truss volume Concrete slab
Truss assembled
Web members 1
Top Chords
Surveying
Tripods
4 tripods
made
9
Forks in truss
10
Finding forks
In wanting to make use of the inherent forms of trees, it was important to understand those shapes from an early stage. A general survey of the forks available informed the design process and aided decisions as to which forks would be felled. With forks on the ground, a thorough 3D scan of each allowed us to work directly with their form.
11
12
Hooke’s trees Hooke Park contains approximately fifteen species of trees - a diverse mix of conifers and broadleafs. Although all species exhibit some kind of branching, only broadleafs produce the kind of forks explored in this project. In studying the species breakdown, and in conversation with Chris Sadd (forester), Charley Brentnall (Make Tutor) and Arup (Engineers) beech was determined as the most suitable species to work with. Wanting to work with found forms, it was important to establish an understanding of what forms beech forks offered. A rough survey was carried out in two compartments photographing forks and assigning them a grade of A, B or C.
= 5000 m2 of forest
Beech
Broadleaf
Conifer
Beech
Douglas fir
Corsican pine
Spruce
Larch
Red oak
Ash
Sitka spruce
Alder
Sycamore
Oak
Red cedar
Poplar
Broadleaf mix
Sweet chestnut
13
Though this grading was helpful in providing initial direction, it was clear that a way to generate an approximate digital representation of forks in standing trees was needed. Using an iPhone app, an approach was developed by which an outline of each fork traced on a photograph in Rhino could be properly scaled and its skew corrected. With this, a survey of all but one of Hooke Park’s beech compartments was carried out. Shown above, while surveying the woods, a rough map was maintained of each fork documented.
14
Fork Name: 08_D02 Date & Time: Thu May 7 19:40:09 BST 2015 Position: +050.79502째 / -002.67711째 Altitude: 184 m Azimuth/Bearing: 064 deg N64E 1138 mils (True) Elevation Angle: +26.5째 Horizon Angle: -00.3째 Zoom: 1X
15
7_A03
08_A03
08_A13
08_A14
08_A16
8_A18
08_C04
08_C05
08_C09
08_C14
8_D02
08_D03
08_D06
09_B04
09_F06
9_F09
09_F10
09_G03
09_G05a
09_G05b
9_G08
09_G16
09_G17a
10_E01
10_E03
0_E06
10_E07
11_A19
11_A22
11_A26
1_A28
11_B03
11_B15
11_B25
11_B26
16
20
18
16
Photo taken
14
12
10
Traced and corrected
08
06
04
02
00 18
Distortion corrected
16
14
12
10
08
06
04
02
00
Approximate FOV for 204 survey photos (1m grid)
Height to centre of fork (1m increments)
Photographed from the ground, each of the photos’ distortion was corrected using the angle at which it was taken, a distance from the stem and the camera’s FOV.
17
Forks= broken surveyed fork From the photos taken in surveying, an = fork approximate geolocation of each fork was extracted and mapped - ensuring they could be found again. A Grasshopper script was developed to combine the 204 polylines with each fork’s location. As each of the polylines had been traced with the same number of lines, the script was able to simultaneously evaluate criteria of all of them. By having GPS positions within this scripting, search parameters could be applied to the collection and live mapped - eg. where are all of the forks with over 30 deg opening?
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07_A01
07_A02
07_A03
08_A01
08_A02
08_A03
08_A04
08_A05
08_A06
08_A07
08_A08
08_A09
08_A10
08_A11
08_A12
08_A13
08_A14
08_A15
08_A16
08_A17
08_A18
08_A19
08_A20
08_B01
08_B02
08_B03
08_B04
08_B05
08_B06
08_B07
08_B08
08_C01
08_C02
08_C03
08_C04
08_C05
08_C06
08_C07
08_C08
08_C09
08_C10
08_C11
08_C12
08_C13
08_C14
08_D01
08_D02
08_D03
08_D04
08_D05
08_D06
08_D07
09_A01
09_A02
09_A03
09_A04
09_A05
09_A06
09_A07
09_A08 09_B01a 09_B01b 09_B02
09_B03
09_B04
09_B05
09_B06
09_B07
09_C01
09_C02
09_C03
09_D01
09_E01
09_E02 09_F01a 09_F01b 09_F02
09_F03
09_F04
09_F05
09_F06
09_F07
09_F10
09_G01
09_G02
09_G03
09_G04 09_G05a 09_G05b 09_G06
09_G07
09_G08
09_G09
09_G10 09_G11a 09_G11b 09_G12
09_G13
09_G14
09_G15
09_G16 09_G17a 09_G17b
10_A01
10_A02
10_A03
10_D01
10_D02
10_E01
10_E02
10_E03
10_E04
10_E05
10_E06
10_E07
10_E08
10_E09
11_A01
11_A02
11_A03
11_A04
11_A05
11_A06
11_A07
11_A08
11_A09
11_A10
11_A11
11_A12
11_A13
11_A14
11_A15
11_A16
11_A17
11_A18
11_A19
11_A20
11_A21
11_A22
11_A23
11_A24
11_A25
11_A26
11_A27
11_A28
11_A29
11_B01
11_B02
11_B03
11_B04
11_B05
11_B06
11_B07
11_B08
11_B09
11_B10
11_B11
11_B12
11_B13
11_B14
11_B15
11_B16
11_B17
11_B18
11_B19
11_B20
11_B21
11_B22
11_B23
11_B24
11_B25
11_B26
11_B27
11_B28
11_B29
11_B30
11_B31
11_B32
11_B33
12_A01
12_A02
12_A03
12_A04
12_A05
12_B01
12_B02
12_B03
09_F08
09_F09
Line = 40 forks selected from analysis script.
12_B04
12_B05
12_B06
12_B07
12_B08
12_B09
12_B10
12_B11
12_B12
12_B13
12_B14
12_B15
12_B16
12_B17
12_B18
Colour = 25 forks felled and 3D scanned.
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07_A03
08_A03
08_A13
08_A14
08_A16
08_D02
08_D03
08_D06
09_B04
09_F06
09_G08
09_G16
09_G17a
10_E01
10_E03
11_A28
11_B03
11_B15
11_B25
11_B26
The 40 forks to be considered for felling.
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08_A18
08_C04
08_C05
08_C09
08_C14
09_F09
09_F10
09_G03
09_G05a
09_G06
10_E06
10_E07
11_A19
11_A22
11_A26
12_A03
12_A04
12_B05
12_B08
12_B13
The next 4 pages show sample evaluations applied to the 40 forks which were eventually selected from this script.
21
17.1°
24.8°
23.6°
27.2° 60.2°
07_A03
08_A03
08_A13
08_A14
08_A16
30.1° 29.1°
27.6°
21.4° 25.8°
08_D02
08_D03
20.2°
08_D06
09_B04
09_F06
23.1° 22.4°
17.9° 21.8°
09_G08
09_G16
09_G17a
23.3°
10_E01
17.1°
10_E03
15.8°
33.4° 21.6°
11_A28
11_B03
11_B15
11_B25
Fork opening range: 14.9° - 60.2° (avg. 24.5°)
22
11_B26
26.2° 25.7° 25.6°
32.0°
08_A18
08_C04
08_C05
22.3°
08_C09
08_C14
23.9° 22.2°
23.5°
09_F09
09_F10
09_G03
21.7°
09_G05a
32.6°
09_G06
23.3°
22.8°
20.6°
26.7° 23.1°
10_E06
10_E07
11_A19
14.9°
11_A22
11_A26
23.4°
18.4°
22.5° 24.6°
12_A03
12_A04
12_B05
12_B08
12_B13
An important criteria in selecting forks was the angle of opening between branch and stem. As most forks have curved limbs, it is difficult to define a single angle - as a change of one’s length results in a change of angle.
23
07_A03
08_A03
08_A13
08_A14
08_A16
08_D02
08_D03
08_D06
09_B04
09_F06
09_G08
09_G16
09_G17a
10_E01
10_E03
11_A28
11_B03
11_B15
11_B25
11_B26
525
24
Diameter range
100
08_A18
08_C04
08_C05
08_C09
08_C14
09_F09
09_F10
09_G03
09_G05a
09_G06
10_E06
10_E07
11_A19
11_A22
11_A26
12_A03
12_A04
12_B05
12_B08
12_B13
The script was also capable of evaluating a fork’s diameter at a given interval. Providing this information to Arup they were able to begin to accurately evaluate forks performance.
25
Felling with Chris With this shortlist of 40 forks prepared, we returned to the woods with Hooke Park’s Forester, Christopher Sadd. First revisiting each of the trees which had been surveyed to ensure the accuracy of the initial survey, and to observe any noticeable defects which had been missed out in the first photos - a number of forks were omitted from the original list and a few added based on in the field observations. Additionally, another few were ruled out for forestry reasons - their removal having a potentially negative impact on the trees surrounding them. In total, 25 forks were successfully harvested.
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27
Felled forks 25 forks were successfully harvested from throughout Hooke Park. In the felling process, 6 trees resulted in significant damage upon impact causing the loss of 7 forks.
07_A01
08_A15
08_C04
08_D07
09_C01
09_G01
09_G16
11_A01
11_A18
11_B06
11_B23
12_B02
07_A02
08_A16
08_C05
09_A01
09_C02
09_G02
09_G17
11_A02
11_A19
11_B07
11_B24
12_B03
07_A03
08_A17
08_C06
09_A02
09_C03
09_G03
09_G17
11_A03
11_A20
11_B08
11_B25
12_B04
08_A01
08_A18
08_C07
09_A03
09_D01
09_G04
10_A01
11_A04
11_A21
11_B09
11_B26
12_B05
08_A02
08_A19
08_C08
09_A04
09_E01
09_G05
10_A02
11_A05
11_A22
11_B10
11_B27
12_B06
08_A03
08_A20
08_C09
09_A05
09_E02
09_G05
10_A03
11_A06
11_A23
11_B11
11_B28
12_B07
08_A04
08_B01
08_C10
09_A06
09_F01
09_G06
10_D01
11_A07
11_A24
11_B12
11_B29
12_B08
08_A05
08_B02
08_C11
09_A07
09_F01
09_G07
10_D02
11_A08
11_A25
11_B13
11_B30
12_B09
08_A06
08_B03
08_C12
09_A08
09_F02
09_G08
10_E01
11_A09
11_A26
11_B14
11_B31
12_B10
08_A07
08_B04
08_C13
09_B01
09_F03
09_G09
10_E02
11_A10
11_A27
11_B15
11_B32
12_B11
08_A08
08_B05
08_C14
09_B01
09_F04
09_G10
10_E03
11_A11
11_A28
11_B16
11_B33
12_B12
08_A09
08_B06
08_D01
09_B02
09_F05
09_G11
10_E04
11_A12
11_A29
11_B17
12_A01
12_B13
08_A10
08_B07
08_D02
09_B03
09_F06
09_G11
10_E05
11_A13
11_B01
11_B18
12_A02
12_B14
08_A11
08_B08
08_D03
09_B04
09_F07
09_G12
10_E06
11_A14
11_B02
11_B19
12_A03
12_B15
08_A12
08_C01
08_D04
09_B05
09_F08
09_G13
10_E07
11_A15
11_B03
11_B20
12_A04
12_B16
08_A13
08_C02
08_D05
09_B06
09_F09
09_G14
10_E08
11_A16
11_B04
11_B21
12_A05
12_B17
08_A14
08_C03
08_D06
09_B07
09_F10
09_G15
10_E09
11_A17
11_B05
11_B22
12_B01
12_B18
28
Fork: 12_A03 Forks were brought back to the yard as large as we could manage to allow flexibility approximately 6 m long and over half a ton
29
Going in circles This image shows the sequence in which forks were felled. As the whole process was an ongoing negotiation with Chris as to the best trees, and with changing standards for suitable forks in working with Arup, we ended up traveling in circles
Campus
= fork = broken fork
30
The inside of fork 08_A16. In total, 6 trees including 7 forks were broken in the felling process. In a number as above, damage and rot was exposed which might not have been noticed
08_A16
08_D05
09_B05
09_E02
09_G05a
09_G05b
11_B19
31
08_D02 scan with 57118 faces Each fork was prepared for the organisation script by adding three reference points which refer to physical holes in the forks and generating centrelines for each of their limbs
32
Organizing forks
Instead of allowing the forks’ forms to directly generate the overall geometry, the Fork Truss organizes 20 of them within a volume which has been designed with their size and shapes in mind.
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08_A03 42906
08_A12 68004
08_A13 61610
08_A14 37442
08_A20 54368
08_C05 44758
08_C11 64726
08_C14 56550
08_D03 61282
09_B04 56416
09_F09 56860
09_G15 61088
10_E01 64714
10_E07 42924
11_A12 41326
11_A29 52944
11_B03 56962
11_B06 65684
11_B09 63414
11_B16 63026
11_B25 66472
12_A03 63582
12_B10 55994
12_B13 55726
25 final 3D fork scans
34
Early versions of the truss were populated manually with polylines from the photo survey. While harvesting and scanning the 25 final forks, a script was developed which was capable of dynamically organizing them.
35
1 First point - move
Second point - rotate
3
2 1 Evaluate - deviation from target curves Third point - rotate
Based on the fork’s three limbs, a placement strategy was established by which a fork finds three points of contact with two target curves by three sequential transformations.
36
The scripting process was progressed from being capable of solving one fork at a time to solving the whole truss - this grid depicts steps along the way.
37
38
17 Fork Truss iterations With scans prepared for all 25 forks, the organization script was run to generate 17 different iterations of the truss. In considering the forks sizes, it was determined that the truss would be made up of 20 forks: six down each of the two outer chords, and two along each of four inner chords. All seventeen overlaid in this image, the variation within those twenty positions is visible. In working with Arup, truss iteration 9.1 was selected as the best arrangement. This version was then taken through a number of further developments before arriving at the built truss – 9.1F.
39
1
2
3
4
450 mm
40
6
6.1
7
7.1
7.2
8
8.1
9
9.1
9.1F
9.2
125 mm
10
10.1
10.2
1
2
3
4
6
6.1
7
7.1
7.2
8
8.1
9
9.1
9.1F
9.2
10
10.1
10.2
These images show each truss iteration’s local colour, these models allowed Arup to accurately in the drawing above and graph to the left, 9.1F than any other - with both fewer very large
fork diameters. Layered by evaluate the truss. Visible has a more even distribution and very small sections.
41
8
08_A03
18
08_A12
14
08_A13
17
08_A14
9
08_A20
18
08_C05
7
08_C11
18
08_C14
18
08_D02
18
08_D03
8
09_B04
18
09_F09
18
09_G15
17
10_E01
16
10_E07
16
11_A12
15
11_A29
14
11_B03
14
11_B06
12
11_B09
12
11_B16
14
11_B25
16
12_A03
14
12_B10
11
12_B13
Organizations This diagram attempts to make some sense of the information generated in outputting 18 distinct iterations of the truss (1-10.2). While a number are similar, each contains a unique arrangement of the 25 forks. On the opposite page, the graph above outlines which forks appear in each iteration of the truss - listing them alphabetically, with blanks indicating a fork left out of that iteration. In the graph below it, the order of these selected 20 forks has been rearranged to describe the exact position (A-T) in which each of the 20 forks included in the truss has been placed. Of note, is the absence of forks 10_E01, 10_E07 and 11_A29 in 9.1F. Three of the more commonly placed forks in other iterations, As the truss was finalized, a number of defects were found in these forks causing their manual exchange.
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A B C D E F G H I J K L M N O P Q R S T
08_A03 08_A12 08_A13 08_A14 08_A20 08_C05 08_C11 08_C14 08_D02 08_D03 09_B04 09_F09 09_G15 10_E01 10_E07 11_A12 11_A29 11_B03 11_B06 11_B09 11_B16 11_B25 12_A03 12_B10 12_B13
1
2
3
4
6
6.1
7
7.1
7.2
8
8.1
9
9.1
9.1F
9.2
10
10.1
10.2
A B C D E F G H I J K L M N O P Q R S T
43
08_A03
08_A12
08_A13
08_A14
08_A20
08_C05
08_C11
08_C14
08_D02
08_D03
09_B04
09_F09
09_G15
10_E01
10_E07
11_A12
11_A29
11_B03
11_B06
11_B09
11_B16
11_B25
12_A03
12_B10
12_B13
Range of positions occupied by each fork in the 18 iterations
44
E
08_A03
08_A12
10_E01
08_A13
10_E07
A
N
P
F
M
D
G
K
T
I
08_A14
08_A20
08_C05
08_C11
08_C14
08_D02
08_D03
09_B04
09_F09
09_G15
11_A12
Q
11_A29
11_B03
11_B06
11_B09
11_B16
11_B25
12_A03
12_B10
12_B13
C
R
O
S
H
L
B
J
Organization of forks in the built truss — 9.1F
45
6
5
4
3
2
1
0
Position: A Fork: 08_A14 Weight: 200kg
Position: B Fork: 12_B10 Weight: 260kg
Position: C Fork: 11_B03 Weight: 150kg
Position: D Fork: 08_D02 Weight: 320kg
Position: E Fork: 08_A12 Weight: 190kg
Position: K Name: 09_B04 Weight: 220kg
Position: L Fork: 12_A03 Weight: 170kg
Position: M Fork: 08_C14 Weight: 320kg
Position: N Fork: 08_A20 Weight: 180kg
Position: O Fork: 11_B09 Weight: 135kg
6
5
4
3
2
1
0
Meshes above illustrate the portion of each fork selected to fabricate truss iteration 9.1F. A wide range of shapes, each is directly related to its position within the truss.
46
6
5
4
3
2
1
0
Position: F Fork: 08_C11 Weight: 215kg
Position: G Fork: 08_D03 Weight: 160kg
Position: H Fork: 11_B25 Weight: 280kg
Position: I Fork: 09_G15 Weight: 260kg
Position: J Fork: 12_B13 Weight: 255kg
6
5
4
3
2
1
0
Position: P Fork: 08_C05 Weight: 200kg
Position: Q Fork: 11_A12 Weight: 270kg
Position: R Fork: 11_B06 Weight: 275kg
Position: S Fork: 11_B16 Weight: 165kg
Position: T Fork: 09_F09 Weight: 320kg
Consistently longer, A to L are those which form the outer chords of the truss. M to T are the inner chords, and use more open angle forks to allow forks to cross in the groin
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Output geometry With a final fork organization selected, a Rhino model was output with the centrelines, reference points, meshes and three new diameter reference circles in order to inform the robotic fabrication process.
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Curve D_2 Circle D_9
Point D_6
Curve D_1
Circle D_7 Point D_4
Curve D_0
Point D_5
Circle D_8
Mesh D_3
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Assembly jig
Robot cell
3D scan image generated by Emmanuel Vercruysse
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Assembling forks
Based on this overall model, the robotic arm was used to mill the connection geometries that would be necessary to join a fork to those around it. With all of its components prepared, the Fork Truss was preassembled in two halves in the Big Shed.
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Front half assembly In order to assemble these large pieces precisely, it was determined that all ten forks of one half would need to be supported in their respective positions before connections could be made. In order to facilitate this, a large jig was constructed which would allow support points to be set out accurately in three dimensions - recreating a rhino model.
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01
02
03
04
05
06
07
08
09
10
11
12
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14
15
16
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18 sheets of OSB were CNC’d with reference geometry from a Rhino model. The underside of each was roughly supported by adding blocking where it seemed likely that support or a tie point might be needed. Two sheets without pockets were instead added to stabilize the frame.
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Jig assembled Leaving room for the telehandler to operate, the assembly jig was constructed in the Big Shed. A rough frame of 50 x 100 mm timbers was constructed on to which the OSB sheets could be aligned and fastened. This photo shows the support points being prepared for the assembly of the rear half of the truss. Each fork is supported by three vertical posts which are precisely positioned to line up with three holes milled into each fork by the robotic arm.
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A:08_A14
B:12_B10
C:11_B03
D:08_D02
E:08_A12
F:08C11
I:08_D03
H:11_B25
G:09_G15
L:12_B13
K:09_B04
J:12_A03
M:08_C14
N:08_A20
O:11_B09
P:08_C05
Q:11_A12
R:11_B06
S:11_B16
T:09_F09
Each fork is oriented on the assembly jig by its three vertical support points.
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M
A N
B
C G
H
O
P I
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Pulled in all directions, front half of the truss held loosely together. Weighing approximately 300kg, each fork was lifted in to place by the telehandler. In order to ensure the precision of the entire assembly, all of the forks and top chords were loosely positioned on the jig together before any connections were made. Working around the truss with sledge hammers, and ratchet straps, the various pieces were pulled in to their exact location. With all of the pieces confidently positioned, connections were made. Each had been set out by the robot - milling holes into one of the two forks to be joined - allowing the determination of its final orientation in place by finishing the other half of the connection. With the primary connections completed, additional web members were fixed in place, and the truss half eventually removed from the Big Shed. The assembly jig was then cleared off and set up anew for assembly of the second half.
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1. Jig fully set up
2. First two forks supported
3. Third fork added
4. Fourth fork added
5. Crossing groin forks added
6. Eight forks - first full side
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7. Complete chord of three forks
8. Final fork positioned
9. First top chord added
10. Second top chord added
63 11. All top chords added
12. All web members added
3D scan of the rear half of the truss in the Big Shed
3D scan image generated by Emmanuel Vercruysse
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Ready to move All of its pieces joined together, the front half’s vertical supports are removed. In preparation for transport to site, temporary additional bracing is added.
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Image: Valerie Bennett
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Twenty distinct beech forks organized within an arched Vierendeel like truss. The Fork Truss spans 25 m x 10 m, and rises to 8.5 m at its zenith.
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Truss by the numbers 0
15
204
Major injuries sustained during the build
Dominant tree species found in Hooke Park
Number of beech forks identified around Hooke Park
2
18
400
Number of truss halves preassembled in the Big Shed.
Number of OSB sheets used to construct the Assembly Jig.
Cubic meters of wood chip to be stored - one year’s supply
3
20
1300
Reference holes drilled in to each fork.
Positions within the truss occupied by forks
Length of auger bit needed to finish truss connections (MM)
5
23
7000
Days working on site to erect the pieces of the truss
Piece polyline used to trace forks in the initial survey
Approximate weight of the two truss halves (KG)
6
31
56,635
Axes of rotation of Hooke Park’s robotic arm
Number of beech trees felled in order to harvest 25 forks
Average number of faces in full 3D scan meshes of forks
9
42
9,000,000
Ash trees accidentally documented in surveying
Cubic meters of concrete within the truss’ slab
Viewers of BBC Countryfile’s piece on the Wood Chip Barn
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Number of curves that define the truss’ overall volume
Approximate age of beech trees felled
Projection of OMA’s ‘European Flag’ on the truss.
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Tool path script
Tools paths
Robot cell prepared
FABRICATION NOTES With a final truss organization selected, the robotic arm machined connection
3D scanning
geometries in to each fork to
Robot fabrication
define their relationships to each other. While digitally fabricated, the truss was pre-assembled in two halves in the Big Shed before eventually being erected on site. Connection script
.3DM
Connection mockup
Truss Organized
17 iterations
Scaffold design
Engineer input
Final truss model
.3DM Assembly jig
Final truss volume Concrete slab
Truss assembled
Web members 1
Top Chords
Surveying
Tripods
4 tripods
made
Forks in truss